How do I install the Principle Prove It skill?

Run npx skillmds@latest add edbertchan/principle-prove-it in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Principle Prove It safe to use?

This skill has not completed SkillMD's automated safety review yet. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Principle Prove It?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Principle Prove It free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Principle Prove It?

EdbertChan (@edbertchan) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Principle Prove It by edbertchan — Agent Skill

Name: Principle Prove It
Author: EdbertChan

Principle Prove It

Apply before any claim about code, systems, or history. No claim without same-turn evidence; a hedge is a trigger to verify, never a place to stop. Routes the four investigation products that build the evidence. Unlike the other principles this one auto-fires: it must intercept a claim as it forms, not be named after the fact.

EdbertChan c3fe5bf 5 files · 9.0 KB Updated Sep 17, 2026

File contents

Prove It

A claim is settled only when the evidence for it is in the same message. Everything else is a hypothesis and must say so.

Why: the cheap signal always stands in for the expensive one. A build passes and gets reported as "it works." A file exists and gets reported as "it's wired up." A name matches and gets reported as "that's the bug." Each substitution is individually reasonable and collectively how wrong answers reach the user with confidence attached.

The gate

Before writing any claim of the form "this is fixed," "this works," "the cause is X," "it's merged," "N are running" — you must already have, in the same message, one of:

A command run this turn, with its real pasted output. Not summarized.
A file:line read this turn, named with the ref it was read at.
A test name plus its real pass/fail line from the runner.

Otherwise write UNVERIFIED: immediately before the claim. There is no softer wording. The full evidence rules live in engine/CLAUDE.core.md and are always loaded; this file is the judgment half plus the routing below.

A hedge is a trigger. "I think," "probably," "should work" mean run the check now, not lower the confidence and continue.

Absence of output is not proof of success. A command that printed nothing needs its exit code shown.

What builds the evidence

The gate says what counts. It does not gather anything. Four product skills do that, each fanning out to parallel subagents and returning the shape in corpus/skills/principle-prove-it/references/finding-shape.md:

Product	Question	Returns
`how`	How does this work now?	The mechanism you must exercise
`why`	Why is it shaped this way?	The constraint you must not break
`alternatives-considered`	What else could this be?	Options, each labeled considered or invented
`spike-and-validate`	Does the invented one hold?	A throwaway that ran, and its real output

They compose in that order and each is optional. A one-line fix needs none of them. A claim about a subsystem nobody on the team has read needs how before anything else.

The pairing that matters: alternatives-considered generates, so it can always produce three plausible options and none of them are evidence. spike-and-validate is its gate. An invented option that reaches a decision without a spike is exactly the manufactured evidence this principle exists to stop.

prove-it-ship-gate — the done/shipped auto-route for live side effects.
principle-fix-root-causes — reproduce before explaining.
principle-sequence-verifiable-units — end each unit in a check.
Mechanical enforcement: engine/hooks/prove-it-ship-gate, engine/hooks/hedge-runs-prove-it, engine/hooks/diu-stop.

---name: principle-prove-itdescription: Apply before any claim about code, systems, or history. No claim without same-turn evidence; a hedge is a trigger to verify, never a place to stop. Routes the four investigation products that build the evidence. Unlike the other principles this one auto-fires: it must intercept a claim as it forms, not be named after the fact.---# Prove ItA claim is settled only when the evidence for it is in the same message.Everything else is a hypothesis and must say so.**Why:** the cheap signal always stands in for the expensive one. A buildpasses and gets reported as "it works." A file exists and gets reported as"it's wired up." A name matches and gets reported as "that's the bug." Eachsubstitution is individually reasonable and collectively how wrong answersreach the user with confidence attached.## The gateBefore writing any claim of the form "this is fixed," "this works," "thecause is X," "it's merged," "N are running" — you must already have, in thesame message, one of:1. A command run this turn, with its real pasted output. Not summarized.2. A `file:line` read this turn, named with the ref it was read at.3. A test name plus its real pass/fail line from the runner.Otherwise write `UNVERIFIED:` immediately before the claim. There is nosofter wording. The full evidence rules live in `engine/CLAUDE.core.md` andare always loaded; this file is the judgment half plus the routing below.**A hedge is a trigger.** "I think," "probably," "should work" mean run thecheck now, not lower the confidence and continue.**Absence of output is not proof of success.** A command that printednothing needs its exit code shown.## What builds the evidenceThe gate says what counts. It does not gather anything. Four product skillsdo that, each fanning out to parallel subagents and returning the shape in`corpus/skills/principle-prove-it/references/finding-shape.md`:| Product | Question | Returns || --- | --- | --- || `how` | How does this work now? | The mechanism you must exercise || `why` | Why is it shaped this way? | The constraint you must not break || `alternatives-considered` | What else could this be? | Options, each labeled considered or invented || `spike-and-validate` | Does the invented one hold? | A throwaway that ran, and its real output |They compose in that order and each is optional. A one-line fix needs noneof them. A claim about a subsystem nobody on the team has read needs `how`before anything else.The pairing that matters: `alternatives-considered` **generates**, so it canalways produce three plausible options and none of them are evidence.`spike-and-validate` is its gate. An invented option that reaches a decisionwithout a spike is exactly the manufactured evidence this principle existsto stop.## Related- `prove-it-ship-gate` — the done/shipped auto-route for live side effects.- `principle-fix-root-causes` — reproduce before explaining.- `principle-sequence-verifiable-units` — end each unit in a check.- Mechanical enforcement: `engine/hooks/prove-it-ship-gate`, `engine/hooks/hedge-runs-prove-it`, `engine/hooks/diu-stop`.

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